Adjustable shaft mounting



s. E. PETTIGREW ADJUSTABLE SHAFT MOUNTING Filed April 13, 1951 //\/z/5/\/ TUE 5.5:. PE'TTIGEEW ,4 7- TU/F/Vi/ Patented Oct. 12, 1954 ADJUSTABLE SHAFT MOUNTING Sydney E. Pettigrew, Portland, reg., assignor of one-half to Don B. Card, Portland, Oreg.

Application April 13, 1951, Serial No. 220,837

1 Claim. 1

This invention relates generally to tighteners for endless chains and belts and particularly to a means whereby the axes of the pulleys or sprocket wheels may be held along a given line.

The main object of this invention is to provide a simple and effective means for tightening a belt, chain or conveyor without changing the position of the runs of the chain or belt during or after the tightening operation.

The second object is to make it possible to adjust the elevation of the end of a belt or chain and to hold it there during subsequent tightenmg.

I accomplish these and other objects in the manner set forth in the following specification as illustrated in the accompanying drawing, in which:

Fig. 1 is a fragmentary section through the device taken along the line l! in Fig. 2.

Fig. 2 is a section taken along the line 2--2 in, Fig. 1.

Fig. 3 is a diagrammatic view showing the relative positions of the related parts.

Like numbers of reference refer to the same or similar parts throughout the several views.

Referring in detail to the drawing there is shown a representative form of side frame it which may, for example, be part of a conveyor. To the side frame ill is secured a concentric ring H which is mounted concentrically with relation to the large hole l2 formed in the side frame I0, to which it is secured by means of the rivets l3.

Within the ring H and against the frame H3 is disposed the revolvable disk It having holes I 5 formed around its outer edge, said holes being equidistantly spaced and adapted to receive the clamping screws, for which there are provided tapped holes H in the frame Ill.

Formed in the disk It is the bevelled hole 18 which is eccentric with relation to the exterior of the disk M. In the hole is is the eccentric flange [9 of a bearing housing 20, within which is mounted a self-aligning bearing 2 I, which supports the shaft 22 on which, in this instance, is mounted a V-grooved pulley 23 which carries a belt 24. The outer edge 25 of the eccentric flange I9 is bevelled to match the bevelled hole H3 in the disk M. The tightening of the screws i6 clamps the flange IS in a fixed position due to the contacting bevelled edges l8 and 25.

Around the interior of the ring I I are disposed the numbers 26 which extend around 180 of the ring. The ring I4 has an indicating arrow 2'! which can register with the numbers 25.

The inner edge of the bevelled hole 18 of the disk M has numbers 28 formed around its circumference, while the outer edge of the eccentric flange It has an indicating arrow 29 formed thereon which can register with the numbers 2 8. In Fig. 3 is shown somewhat diagrammatically the operation of the device wherein the straight line 38 represents the travel of the shaft center and the semi-circular line 3! rep-resents the path of travel; that is to say, the radii of eccentricity form the sides of toggle joints or braces between the housing 20 and the frame It]. If, for example, it is desired to move the center of the shaft 22 along the line 30 for the purpose of adjusting the tension on the belt 24, or along the chain or belt carried by the shaft 22, then the first step is to move the disk [4, for example, until the arrow 21 registers with its number 2 and then put the screws l6 into place in the holes IS without tightening, after which the indicator 29 is moved to its corresponding number 2 along the edge 13 and the screws I6 tightened.

It will be noted that the inner set of numbers 28 extend around the complete circumference of the hole I8, while the outer set of numbers 26 extend only around one-half of the interior of the ring II; that is, one disk must be moved twice as far as the other in order to maintain the center of the shaft 22 along the line 30. It can thus be seen that by a very simple and inexpensive arrangement a belt may be tightened or loosened any predetermined amount along the line 30, or the shaft axis may be raised or lowered with relation to the line 30 and thereafter maintained at this level by merely maintaining a fixed relationship between the numbers on the disk and their correspondingindicating arrows; that is to say, if a 4 on the inner disk and a 2 on the outer disk would give the desired position for the shaft 22, then any similar combination of numbers separated by 2, such as '7 and 5, 3 and 1, etc., would hold the shaft 22 at the same elevation above or below the line 30.

I claim:

A shaft mounting comprised of a side frame, a journal having an eccentric flange formed thereon, a revolvable disk having a circular opening therein'eccentric with relation to the circumference of said disk and within which said flange can turn, a journal on said frame for said disk, said disk supported by said frame and having holes formed concentric with and equi-distantly around said disk, screws for clamping said perforated disk to said frame, the journal on said frame having a series of calibrations around one References Cited in the file of this patent hundred eighty degrees thereof corresponding ENT k with the spacing of the holes in said disk, said UNITED STATES PAT s disk having graduations around the full three Number Name Date hundred sixty degrees of the opening therein 5 276,292 Seymour Apr. 24, 1383 with angular spacing two times as great as the 844,892 Handel 1907 angular spacing of the holes in said disk whereby 1171347 Morse 1916 said journal and disk may be revolved in oppo- 1571557 Paul 1926 site directions and equal number of calibrations 2,538,675 Engel J 1951 and cause the axis of said shaft to move in plane. 10 FOREIGN PATENTS Number Country Date 139,363 Great Britain Mar. 4, 1920 

